The present invention relates to DC-DC switchmode power converters.
Switchmode DC-DC power converters have the advantages of high power conversion efficiencies and small size. Very frequently the converters are used in applications which require well regulated, uninterrupted output voltages despite the fact that the input voltages may be subjected to severe transients. If the transient excursions from the steady state input levels have large amplitudes and/or long durations, the circuit design of the DC-DC converter and the selection of components result in a design that has less than optimal efficiency when the converter is operated at steady state conditions. Additional requirements for local energy storage resulting from the interruption of input power can impose more severe input voltage requirements, below the power source minimum voltage transient level and thus further aggravate the problem of creating an efficient design. In addition to reduced efficiency when operated at steady state conditions, the converters designed to accommodate a large input voltage range with energy storage requirements are usually physically larger.
Applications which impose a wide variation of input voltage on the electrical power system are usually those in which there is a power limited source, such as; a solar array, aircraft electrical generator or battery source. High efficiency operation is particularly important when the input source is power limited.
It is an object of the present invention to provide a power system that can provide well regulated output voltages from an input source with wide transient variations and achieve a significant overall power efficiency improvement.
It is a further object of the present invention to provide a power system with well regulated output voltages from a wide range of input voltage with a significant size reduction. Applications having a need for greater local energy storage will provide the opportunity for the largest size reduction.